1. Field of the Invention
The present invention relates to a fluid pump suitable for a cooling system that cools heat generating parts.
2. Description of the Related Art
Conventionally many existing fluid pumps for handling a liquid are provided with a motor having a rotor to which an impeller is integrally fixed for rotation together with the rotor, so that the pump vanes of the impeller serve to suction the liquid into a pump chamber via a suction port, and to discharge the liquid out of the pump chamber via a discharge port.
Such pumps can be incorporated in a cooling system that cools heat-generating parts, including a heat-receiving section that absorbs the heat of the heat-generating parts via a liquid refrigerant and a heat-dissipating section that dissipates the heat transferred to the liquid refrigerant, as a means of circulating the liquid refrigerant through the heat-receiving section and the heat-dissipating section. When the liquid refrigerant is circulated through a closed circuit, the cooling system further includes a reserve tank for storing reserve liquid refrigerant to compensate for a decrease in the liquid refrigerant due to evaporation, in addition to the heat-receiving section, heat-dissipating section and fluid pump, as disclosed in Japanese Published Unexamined Patent Application No. 2003-172286, Japanese Published Unexamined Patent Application No. 2003-161284, and Japanese Published Unexamined Patent Application No. 2003-124671 for example. A purpose of employing the reserve tank is to prevent degradation of the cooling performance, since a decrease in the amount of the liquid refrigerant by evaporation results in a lower cooling capacity.
In such a conventional cooling system including a fluid pump, however, the separately installed reserve tank incurs various drawbacks such as an increase in the number of parts as well as in over-all dimensions of the system, and also in the number of connecting points.